The present disclosure relates to an image forming apparatus including a development device developing an electrostatic latent image formed on an image carrier by a developer.
An electro-photographic image forming apparatus is provided with a development device developing an electrostatic latent image formed on an image carrier by a developer. In the development device, the developer is carried on a developer carrier and is supplied to the electrostatic latent image formed on the image carrier. Such a developer carrier may be configured so as to include a rotatable nonmagnetic cylindrical sleeve and a magnet roller fixedly disposed inside the cylindrical sleeve and to carry the developer on a surface of the cylindrical sleeve by magnetic force generated by the magnet roller. The magnet roller has a plurality of magnetic poles arrayed along a circumferential direction of a shaft, and the respective magnetic poles are positioned so as to be located at predetermined positions.
For example, there is a development device configured such that one end of a shaft of a magnet roller is cut and formed into a D-shape, and a position adjusting member provided with an opening engaging with the D-cut end is used to position magnetic poles of the magnet roller. The position adjusting member is a plate metal member such as a plate spring and is used as a conduction member with a restricting blade restricting a thickness of a layer of the developer carried on a surface of a cylindrical sleeve. However, this development device has a problem that the plate spring-like position adjusting member needs to be formed by using metal molds, and thus a cost is increased.
Then, as the position adjusting member, there is a case where a resin-made cover member provided with a hollow boss-like bearing part engaged with a D-cut end is used. In this case, the development device is attached to an apparatus main body of the image forming apparatus by engaging the bearing part with rails provided in the apparatus main body. It is noted that in the case where the resin-made position adjusting member is used, a spring wire is used as a separate member to obtain conduction with the restricting blade.